Yaacov Leiva was cooking in a food truck in the vicinity of all four stabbings when he heard a commotion. He told KVUE he turned around and saw Kendrex White stab the fourth victim right in front of the food truck. That's when he did something unusual. Instead of running or hiding, he jumped out of the truck and followed White.

"I saw when this stuff happened," Leiva said. "I came out the window -- I was yelling at people to move -- to get out the way."

Leiva can remember the scene in vivid detail.

"He had a towel in his pocket," Leiva said. "And every time he stabbed someone he wiped it off."

Leiva told KVUE he then helped police identify White before he filmed the arrest.

"He stabbed four people in less than a block," Leiva said. "(Police) didn't really notice, he was walking towards more people over there. The cop hadn't noticed until we caught his attention."

In the footage provided to KVUE and taken right outside the Jester dining hall, a UT police officer is seen standing behind White in the doorway. He can be heard telling him to drop the knife.

Then Leiva goes inside and gets footage showing White laying on the ground just minutes after the attack.

Leiva told KVUE he pursued White because the alleged attacker seemed too calm and because he didn't want him to get away with it.

"He didn't have a facial expression. He was emotionless," Leiva said. "He didn't seem like he was sorry for what he had done. He was like, 'Oh well, I did what I did and that's that.' He was just blank, and that bugged me a lot."

Tune in to KVUE Wednesday at 10 p.m. to see the full video and to hear the rest of Leiva's story.